1. Technical Field
The present invention relates to a construction of a cooled-air circulating passage directed toward a fresh room in a refrigerator having a freezing room and the fresh room (refrigerating room) therein.
2. Background Art
FIG. 1 is a schematic diagram showing a construction of the conventional refrigerator.
Referring to FIG. 1, the conventional refrigerator consists of an evaporator 1, a duct 3, a freezing room 5, a fresh room 7, a vegetable room 9 and a damper 11. The temperature of the evaporator 1 is set below the temperature of the freezing room 5. High-temperature air is cooled by a compressor and a fan (not shown), so that the cooled air is distributed to the freezing room 5 and the fresh room 7. The air output from each room is returned to the evaporator 1 through the duct 3 and is again cooled by the evaporator 1.
The fresh room 7 and the vegetable room 9 are cooled in a manner that the cooling degree is controlled by an opening-closing of the damper 11. The cooled air flows through the fresh room 7 and the vegetable room in this order. The flow directions of the air are shown by arrow marks in FIG. 1.
Note that the freezing room 5 has the lowest temperature, the fresh room 7 has a temperature that is slightly higher than the freezing room 5, and the vegetable room 9 has a temperature that is slightly higher than the fresh room 7.
FIG. 2 is a timing chart showing the timing and duration of operating elements according to the refrigerator shown in FIG. 1.
FIG. 2, shows the temperature of the evaporator 1 with the compressor and fan being activated and not activated, the state (open or close) of the damper 11 of fresh room 7, the temperature in the fresh room 7 and the temperature of the cooled air blowing into the fresh room 7.
Referring to FIGS. 1 and 2, when the compressor and the fan are switched ON, the temperature of the evaporator 1 is decreased. Then, the damper 11 is opened before the compressor and the fan are operated ON. Thus, the cooled air enters into the fresh room 7. Thereafter, when the fresh room 7 is sufficiently cooled, the damper 11 is closed so that the cooled air from the evaporator 1 does not enter into the fresh room 7. In other words, by shutting off the cooled air entering the fresh room 7, the temperature of the fresh room 7 is controlled.
However, in the conventional refrigerator, there are the following problems:
(1) The cooled air for cooling the fresh room 7 has the same temperature with the cooled air for cooling the freezing room 5. Thus, the passage for the cooled air to pass through the fresh room 7 is controlled by opening and closing the passage, in order that the the temperature of the fresh room 7 is kept at a suitable temperature. As a result thereof, the temperatures in the refrigerator, especially the fresh room 7 fluctuates with a undesirably big range, in other words, difference between the maximum and minimum temperatures of the fresh room 7 is greater than a too much to suitable amount. Moreover, there occurs different temperature distribution inside the fresh room. PA1 (2) Since the temperature of the cooled air blowing into the fresh room is too low, so that the food placed near a blowout opening tends to be frozen. PA1 (3) The circulated air from each room is returned to the evaporator 1 through each different passage. Therefore, each returned air has its own different state, thus creating undesirable dispersion of conditions when each circulated air is returned to the evaporator 1. As a result, the efficiency for the evaporator 1 is deteriorated and a heat exchanging portion is frosted.
As described above, in the conventional refrigerators, the temperature inside the refrigerator especially the fresh room fluctuates undesirably, and the food placed near the cooled-air blowout opening is undesirably frozen, Moreover, the evaporator efficiency is deteriorated and the heat exchanging portion becomes frosted.